Machine for rolling or piercing billets



Oct. 18, 1932. w. R. CLARK 1,832,655

mourns FOR ROLLING on PIERCING BILLE'IS Filed Sept. 27. 1928 4Sheets-Sheet 1 Oct. 18,1932. w. R. CLARK MACHINE FOR ROLLING 0R PIERCINGBILLETS 4 Shee ts-Sheet 2 Filed Sept. 27. 1928 IIIIIIIIIII I II lllva I:

Oct. 18, 1932. wIR. CLARK MACHINE FOR ROLLING OR PIERCING BILLETS FiledSept. 27, 1928 4 Sheets-Sheet 3 Jwuentoo dmm s Oct. 18,1932. w. R. CLARK1,882,655

I MACHINE FOR ROLLING 0R PIERCING BILLETS Filed Sept. 27. 1928 4Sheets-Sheet 4 a I H II I! Q g [i11 ll II' II II II N I l h W/Mk/CQ, M

b ed/ Patented. Oct. 18, 1932 v WALTER n. CLARK, or BRIDGEPOBT,CONNECTICUT MACHINE FOR ROLLING OR PIERCING BILLETS Application filedSeptember 27, 1928. Serial No. 308,737.

My invention relates to a machine for rolling or piercing billets,and'more especially to a machine for rolling round billets of relativelysmall diameter from billets of larger glfilelietel or for piercing roundbillets to form The usual mill for rolling or piercing billets isprovided with two rolls in the form of i above or below the center ofthe billet, where it crosses the same, the rolling or piercing is offcenter, and a guide or third roll must be in contact with the billet tohold it in position, as reactions introduced into the working of thebillet tend to force it further from the center line if not checked by aguide of some kind. This guide is usually a surface against which thebillet bears as it revolves and feeds forward, oran idler roll driven bythe friction of -the billet in contact therewith.

Guides are used on radially opposite sides of the pass frequently whenpiercing takes place on center to prevent anytendency for piercing orrolling off center due to irregular- 3-" ity in the speed of the rollsurfaces or due to bent billets whipping out of center during thepiercing operation.

In the -cross-rolling and piercing of some materials, such as brass,copper, aluminium, zinc, and other substances relatively soft when atpiercing temperatures, therubbing of a guide is injurious to the surfaceof the billet and tube, due, among other causes, to

. some of the metal or oxide of the billet adhering to the guide andcausing. a roughness which scores the following pierced billets.

Whipping of not quite straight billets some-1 times injures theirsurfaces and the billets are often scratched or grooved by contact withthe guides, and by back slip occurring where the forward speed is lessthan the theoretical speed which would be given to the surface of thebillet revolving between the two rolls if there was no resistance to theforward speed.

It is, in general, an object of this invention to provide means forrolling billets in which a relatively soft material may be handledwithout injury to the surface thereof from rubbing or whipping on suchguides as are required to properly direct the material into the rolls.

v A further object of the invention is to give greater feed pressure onthe billet against the piercing point when it is used and to bring aboutless back slippage of the rolls on the billet and faster feeding of thesame. a

' A still further object of the invention is to bring about a machine inwhich the whipping tendency of the billet is reduced and a balancedcondition of the billet brought about,

' whereby higher rolling speeds and piercing may be obtained.

To these and other ends, the invention consist in the novel features andcombination of parts to be hereinafter described and claimed.

In the drawings,

Fig. 1 isa side elevation of a rolling mill according to my invention;

Fig. 2 is a fragmentary v'ew of the same showing a preferred arrangementof the -1netal-reducing rolls and guides;

Fig. 3 is a View of theguide and working rolls from the left-hand end ofFig. 2; Fig. 4 is a view of the guide and working rolls from theright-hand end of Fig; 2;

' Fig. 5 is a view from the left-hand end of Fig. 2;

Fig. 6 is .aview similar to Fig. 2 but showin g a modification;

Fig. 7 is a view from the left-hand end of Fig. i 6, but with certain ofthe parts removed;

Fig. 8 is a View similar to Fig. 2, but showing stillanothermodification;

Fig. 9 is a view taken from the left-hand endofFig.8;

Fig. 10 is a sectional view along line 1010 of Fig. 1;

Fig. 11 is a view of still another modifica tion; and

Fig. 12 is a view of the means used for supporting a piercing point whenthe latter is used in the production of tubing.

Referring then to the drawings in which I have illustrated my inventionby showing a preferred embodimentthereof, and with particular referenceto Figs. 1, 2, 3 and 4, the reference numeral 15 indicates, in general,a rolling mill having a plurality of metal reducing rolls 16, 17 and 18mounted in suitable bearing blocks 19 in mill housing 20, and formingtherebetween a pass in which a round billet may be reduced or a solidbillet pierced. As shown particularly in Fig. 2 of the drawings, rolls16, 17 and 18 are mounted at an angle to one another, and'spirallyarranged with reference to the axis of the billet. The billet whenpassing between the rolls is thus subjected to a cross-rolling action,the result of which is to cause the billet to travel through the passbetween the rolls. In the case of a solid billet being pierced, thebillet just as it leaves the roll encounters a projectile-like steelpoint 21, carried on a long rod 22, over which it is forced, rotatingmeanwhile between the rolls 16, 17 and 18 just ahead of the point. Asshown in the drawings, the rolls are preferably provided with surfacesmade of the frustrums of two cones.

As a suitable means for driving the metal reducing rolls, there isprovided a driving head 23, comprising a pair of frames 24 and 25,having mounted therein a shaft 26 on which are secured relatively largeand rela tively small gears 27 and 28, respectively, the large gear 27being driven from a suitable source of power and the small gear 28driving a plurality of gears 29, 30 and 31, mounted on shafts 32, 33 and34, connected by universal joints 35, 36 and 37 to shafts 38, 39 and 40,which in turn are connected to rolls 16, 17 and 18 by means of universaljoints, of which two, 41 and 42, are shown. Gears 29, 30 and 31 are allof the same size, and thus it will be readily understood without furtherdescription that all of the rolls are driven in the same direction andat the same speed.

Rolls 16, 17 and 18 are arranged about the pass formed therebetween atthe vertices of an equilateral triangle, and thus a balanced rollingcondition is brought about in which each roll counteracts the effect ofthe other rolls in producing off-center rolling. It will be understoodthat the guides and idler rolls usually provided at the working pass maybe omitted, and thus the scoring of the billets which usually takesplace at this point is eliminated.

In order to support the billets as they pass to and from the working orreducing rolls and thereby to prevent whipping, guides are providedherein, either at the point where the billet passes into the workingrolls or at the point where the reduced or pierced billet leaves therolls, or both. Referring to Figs. 2, 3, 4 and 5, which show a preferredform of these guides, the reference numeral 43 indicates a guide framein which are mounted a pair of shafts 44 and 45 supporting rolls 46 and47, while a third roll 48 is mounted above and between rolls 46 and 47,being supported on shaft 49 mounted in yoke 50, pivotally supported onframe 43 by means of rod 51."

In order that guide rolls 46 and 47 may bring the billet into pro eralignment with the pass between the wor ring rolls, frame 43 may beadjusted vertically by means of screw wedges 52 and 53, provided withlock nuts '54 and 55, While guide rolls 48 may be adjusted relatively torolls 46 and 47 by swinging yoke 50 about pivot 51, a convenient meansto this end being provided by way of handle 56, pawl 57 being provided,engaging rack 58 to lock the yoke against movement, and rack 58 beingprovided with a plurality of notches 59 in which the pawl may bereceived. A counter weight 60 may be provided if desired tocounterbalance the weight of guide roll 48.

. Adjacent the outlet end of the mill is a similar arrangement of guiderolls 61, 62 and 63, which may be supported and adjusted in the samemanner as rolls 46, 47 and 48, and which will not, therefore, bedescribed herein in detail. The ends of all the guide rolls are roundedas at 64 in order that the billet may readily pass therebetween withoutbecoming scored.

In order to take up the thrust produced on piercing point 21 and toprovide a ready means for adjusting the point to proper positionopposite the pass between rolls 16, 17 and 1.8, a tail stock 65 (Fig.12) is provided having a thrust bearing 66 which may be adjusted towardsor away from the metal reducing pass by means of adjusting screw 67,having mounted thereon hand wheel 68.

From the above description of the invention it will be readilyunderstood that, owing to the support given to the billet before itenters between the working rolls and after it emerges therefrom,whipping of the billet is effectively prevented, while owing to the factthat the guides may be rotated by the billet no scoring of the lattertakes place.

In Fig.6 I have shownamodificationwhich,

while not having the adj ustability of the form shown in Fig. 2, isparticularly effective in preventing whipping, especially where billetsof substantially constant diameters are operated on. Herein tube 69 isprovided, detachably mounted in sleeve 70, supported at its ends inanti-friction bearings 71 and 72, which are in turn mounted in frame 73.A set screw 74 is provided in sleeve which, upon being unscrewed fromcontact with tube 69 I through opening 75 in frame 73, permits thewithdrawal of tube 69 and the insertion of in whichthe guiding rolls 77,7 8 and79 are concaved inwardly from their ends and spirally arranged asregards the'billet. Herein the relative motion of the guide rolls ispurely rolling, thus effectively preventing scoring.

In Fig. 11 there is shown a form quite similar to that. of Fig. 2, butin which provision is made fortaking care of relatively long billets.Herein a duplex frame 80 is provided, having mounted therein and inalignment,

guide rolls 81 and 82, 83 and 84, and 85 and 86' respectively.

From the foregoing description of my invention and its mode ofoperation, it will be readily understood that I have brought about abalanced condition in the rolling, reducing and piercing of billets inwhich any tendency of rolling off-center is eliminated, together withany tendency of the billets to whip or score. Furthermore, thearrangement is such that bent billets are effectively straightened bythe rotatable guides before and after being acted on by the workingrolls. The form shownin Fig. 8 is particularly effective in this respectin that the guide rolls produce a cross rolling effect on the billetsasthe latter are drawn into the working pass and rotated by the workingrolls. Thus it is possible to speed up .the reduction and piercing ofthe billets, together with the production of more uniform dimensions andsurfaces.

While I have shown and described preferred embodiments of my invention,it is understood that 'it is not to be. limited to all of the detailsshown, but is capable of modification and variation which will liewithin the'spirit of the invention and the scope of the appended claims.What I claim is:

1. In a cross rolling mill for reducing or pass, said guiding meanscomprising three rolls arranged at the vertices of a triangle-betweenwhich the billets are received, the axes of the guiding rolls beingsubstantially parallel to the axes of the billets, said guidingrollsbeing movable relatively to oneanother to accommodate billets ofdifferent diame ters.

2. In a cross rolling mill for reducing or piercing -round,rod-likebillets, a plurality of working rolls arranged to form a working pass,said rolls producing rotary movement in, the billets, a frame, a pair ofguide rolls mounted in said frame in horizontal alignment, said frameand rolls being vertically. adjustable, anda third guide roll mountedabove and between said first named guide rolls and adjustable relativelythereto, the axes of said guide rollsbeing substantially parallel to theaxes of the billets.

3. In a cross rolling .mill for reducing or piercing round, rod-likebillets, a plurality of working rolls arranged to form a working pass,said rolls producing rolling movements in the billets, a frame, apair ofguide rolls mounted in said frame in horizontal align- -ment, said frameand-rolls being vertically adjustable, a third guide roll mounted aboveand between said first named guide rolls and 1 adjustable relativelythereto, the axes of said guide rolls being substantially parallel tothe axes of the billets, and means forsecuring said guide rolls in anyposition of adjustment.

4. In a cross rolling mill for reducing or piercing round, rod-likebillets, a plurality ,of working rolls arranged to form a working pass,said rolls'rotating the billets on their axes and feeding themlongitudinally, and

freely rotatable guiding means for maintaining the billets in alignmentwith said pass, said means being rotated by contact with the billetsabout an axis substantially parallel to the axes of the billets.

5. In a cross rolling mill for reducing or their axes andfreely'rotatable guiding means for maintaining the billets in alignmentwith said pass, the rotary movement of said billets producing rotarymovement of the guiding means upon contact of the billets therewith,said guiding means comprising a plurality of freely rotatable rollsbetween which the billets pass, the axes of said rolls beingsubstantially parallel to the billet axes. V

6. In a cross rolling mill for reducing or piercing round,rodlike'billets, a plurality of working rolls arranged to form a pass,said rolls rotating the billets and freely rotatable guiding means formaintaining the billets in alignment with said pass, said guiding meanscomprising at least three rolls arranged at equal intervals about theaxis of the working pass, the axes of said guiding rolls being1substantially parallel to the axes of the biletsa , 7. In acrossrolling mill for reducing or piercing round, rod-like billets, aplurality of working rolls arranged to form a pass, said rolls rotatingthe billets and freely rotatable guiding means for maintaining thebillets in alignment with said pass, said guiding means comprising atleast three rolls arranged at equal intervals about the axis of theworking pass, the axes of said guiding rolls being substantiallyparallel to the axes of the billets, and means for adjusting saidguiding rolls relativelyto one another to accommodate billets ofdifferent diameters.

8. In a cross rolling mill for reducing or piercing round, rod-likebillets, three or more power-driven working rolls equally spacedradially and circ'umferentially with respect to the billet and arrangedto form a working pass, said rolls rotating the billets-on their axesand feeding them longitudinally, and freely rotatable guiding means formalntaining the billets in alignment with said pass, said guiding meansbeing rotated by contact with the billets about an axis substantiallyparallel to the axes of the billets.

9. In a cross rolling mill for reducing or piercing round, rod-likebillets, three or more power-driven working rolls equally spacedradially and circumferentially with respect to the billet and arrangedto form a working pass, said rolls rotating said billets about theiraxes, and freely rotatable guiding means for maintaining the billets inalignment with said pass, the rotary movement of said billets producingrotary movement of the guiding means upon contact of the billetstherewith, said guiding means comprising a plurality of freely rotatablerolls between which the billets pass, the axes of said rolls beingsubstantially parallel to the billet axes.

In witness whereof, I have hereunto set my hand this 21st day ofSeptember, 1928.

WALTER R. CLARK.

